The filter size for the Summarit should have been the standard easy-to-find 40.5 mm, instead it is the unique-to-Leica, rare-as-hens'-teeth E41. The size for the 135 mm Hektor was always A36. The Summarit filters were discussed on this thread:
I have never owned this lens so have not tried to find them, all I know is they are quite rare! There are lots of A36 filters around, most in less than perfect condition, I have in the past made myself a "new" filter by taking an A36 mount and putting in the new glass from a 35.5 screw-in filter. Then I got a Leitz adapter which allows E39 filters to be used. Your Hektor, by the way, is from 1958.
Last edited by David H. Bebbington; 01-27-2007 at 05:02 PM. Click to view previous post history.
Reason: Added link, corrected 1 spelling error.